If you've been observing the monthly auto industry sales figures we compile every month, there's a noticeable trend: Sales in the luxury/premium auto segment have been dropping steadily since January.

Upon asking a senior executive in the luxury auto industry as to what accounts for this, he cited the impeachment trial of Chief Justice Renato C. Corona as a factor.

Wait, an impeachment trial of the Chief Justice of the Supreme Court is related to the decline of the luxury automobile segment? It's definitely possible, as this points to a well known, but rarely spoken of issue that a sizable portion of luxury auto purchases come from public officials who, of course, prefer keeping the purchase of high profile vehicles as low profile as possible. With SALN, or the Statement of Assets, Liabilities and Net worth becoming such a hot issue, luxury auto sales have been taking a quite a big hit.

The sales figures for the past few months seem to support this theory. In the month of April, brands such as BMW, Lexus, Mercedes-Benz, Porsche and Audi have seen a sharp decline in sales, with one brand actually experiencing a 48% decline when compared to the same month in 2011.

Of course, there are many reasons for sales to drop such as a dip in the economy, but the sales figures of other manufacturers/distributors not in the luxury sector appear to be either picking up or holding steady. Brands such as Toyota, Hyundai, Mitsubishi, Honda and Kia (among others) have sustained sales performances over the same period.

With the impeachment trial threatening to bring many other SALNs to the surface, well, it seems everyone is taking extra care to avoid getting caught in the spotlight.